Vapor condenser and liquid radiator



Aug. 25, 1942. C PR|E I 2,294,350

VAPOR CONDENSER AND LIQUID RADIATOR Filed Nov. 20, 1940' 4 Sheets-Sheet 1 Aug. 25, 1 N. c. PRICE VAPOR CONDENSER AND LIQUID RADIATOR 4 Sheets-Sheet 2 Filed Nov. 20, 1940 INVENTOR W417 Aug. 25, 1942. N. c. PRICE 2,294,350

VAPOR CONDENSER AND LIQUID RADIATOR Filed Nov. 20, 1940 4 Sheets-Sheet 4 $754M CONDENSER STEA EL ECT'R/C TURB/NE GE NE RA TOR Patented Aug. 25, 1942 VAPOR CONDENSER AND LIQUID RADIATOR Nathan C. Price, Hollywood; Calif.

Application November 20, 1940, Serial-No. 366,374

8 Claims.

This invention relates to improvements in vapor condensers and/or liquid radiators, and more particularly to a novel construction and arrangement for such apparatus, wherein air at atmospheric temperature is utilized as the means for absorbing and dissipating the heat. Other phases of the invention relate to novel methods for automatically controlling and stabilizing such apparatus.

It is, therefore, among the primary objects of this invention to provide a novel construction for vapor condensers and/or radiators wherein air at atmospheric temperature is utilized as the cooling medium; to provide an apparatus of the type described of unusual compactness and extreme capacity; to provide anovel means for controlling or regulating such apparatus which will operate automatically to maintain uniform thermal conditions at the condenser or radiator outlet; to provide a control apparatus which will maintain condenser outlet temperatures suificiently below the saturation temperature to prevent vapor locking in the feed water pumps and yet sufficiently high forproper cycle efiiciency;

to provide a more efilcient apparatus for driving auxiliary apparatus in aircraft such as electric generators or engine superchargers; to provide an efiicient means-for waste heat recovery and heating air; and many other objects and advantages as will become more apparent as the description proceeds.

In accordance with the invention, an apparatus is provided which may be adapted with very slight modifications to function either as a condenser for steam or other vapors or as a radiator for liquid cooled internal combustion engines. Furthermore, the invention is suited to assist in aircraft propulsion, or in lift augmentation by providing a noveland efficient means for pumping and adding heat to air for purposes of boundary layer control over an aerodynamic surface. The many disadvantages normally associated with apparatus of this type and which have heretofore restricted'the use thereof have been completely eliminated. This fact in conjunction with the many new advantages re sulting therefrom will be readily understood and appreciated by those skilled in the art after reading the following detailed description of the drawings forming a part of this specification.

In the drawings: Figure I is a longitudinal section through a condenser constructed in accordance with my ment thereof with respect to the cooling fan and the steam turbine.

Figure II is an enlarged sectional View of the fan end of the condenser clearly illustrating the mechanism for varying the pitch of the proeller blades.

Figure III is an enlarged sectional view of the condensate'end of the condenser and illustrates in detail the novel control apparatus incorporated therein.

Figure IV is a sectional View taken on the line IVIV of Figure I to more clearly show the preferred construction of the condenser tu-bes.

' Figure V is a side elevation of an auxiliary steam power unitembodying the condenser of this invention.

Figure VI is a diagrammatic showing of the steam supply control operated by the condenser pressure.

Referring to Figure I, the condenser core [0 is comprised of a plurality of-flattened tubes ll circumferentially disposed with respect to a longitudinal axis AA, the axes of said tubes ll extending parallel to said axis AA, and a plurality of longitudinally spaced, transverse, annular, radiating fins l2 secured to said tubes II and circumferentially spacing same, said tubes H and fins l2 cooperating to form a substantially circular, central recess l4. Disposed within said recess M are a plurality of conoidal diffusers I5,

1 the throats I 5" of which are directed toward, and

invention and showing also the general arrange- .55

diametrically proportioned with respect to a propellertype fan I6 disposed in the end of said recess l4. By this arrangement each diffuser l5 draws off a definite portion of the air at said recess M delivered by the fan I6 and distributes same along the core In. Another advantage is that it permits the use of a very small fan operating at extremely high speeds and prevents recirculation of the air within the recess M. The diifusers l5 also serve as turning vanes and direct the air radially outward between the fins I2. It will be noticed that several of the fins I 2 between adjacent diffuser cones [5 are provided with curled edges I! which protrude into the recess l4 and further assist in guiding and directing the airover-the condenser tubes H. The innermost of the conoidal diffusers l5 serves as a guide for therod I8 which controls the pitch of the fan blades l9, and also as a support for the fan pitch control. mechanism as will be hereinafter described.

Furtherdescribing. the flow of cooling air through the condenser core Ii] it is to be understood that the viscosity of air. increases with the temperature. Accordingly the portion of the core I nearest the fan I6 tends to have a greater pressure drop between the fins I2 due to the higher temperature. The conoidal diffusers I5 receive the air from the fan I6 and distribute it along the core I0 so that the air which receives the greatest energy from said fan I6 is directed to the portion of the core III which has greatest air flow resistance, while the portion of the air emanating from the region nearest the center of the fan I6 is directed to the portion of the core I0 having the least air flow resistance. Accordingly, air is drawn by each diffuser I5 in proportion to the pressure drop to be overcome. This arrangement promotes high fan efliciency and eliminates circulatory flow within the recess I4.

The fan I6 is herein illustrated as being directly driven by a vapor turbine enclosed within a turbine casing 2| the turbine shaft 43 being coaxial and substantially a continuation of the fan shaft 44. In operation the exhausted working vapor passes from the turbine casing 2I into a diffuser 22 which communicates with an annular collector chamber 23 disposed at the fan end of the core I0. Since the ends 24 of the tubes II open into the annular chamber 23, the vapor upon entering said chamber 23 is uniformly distributed to each of said tubes II. This distribution is further improved bythe action of the diffuser 22 in which the residual velocity of the vapor is converted into pressure which forces said vapor through the tubes I I. The vapor in flowing along said tubes II is cooled until upon reaching the ends 25 thereof, remote to the fan I6, it is completely condensed. Annular ducts 26 and 21, disposed around the end of the core I0, collect the condensed vapor, hereinafter referred to as condensate, and conduct same to the condenser outlet 28.

In my preferred construction, the inner surface of the condenser tubes II is extended by means of transverse strips 29 increasing in number toward the condensate ends thereof as is particularly illustrated in Figure IV. Such construction maintains a more uniform pressure drop within said tubes II and increases the preliminary heat transfer. Near the condensate ends of the tubes -I I these transverse strips 29 direct the vapor and condensate in counter flow to the cooling air, as indicated by the dashed arrows 30 (see Figure III), in order to facilitate cooling below the saturation temperature. Referring again to Figure IV, uniform longitudinal spacing of the fins I2 is obtained by providing a plurality of shallow dimples I3.

In'the normal anticipated installation, considerable auxiliary apparatus, such as electric generators, superchargers and the like, may be driven by the turbine 20. Due to the variations in the operating power required by such apparatus, the desirability of having a wide range in condenser capacity will be readily appreciated. Accordingly, in the embodiment herein illustrated, I have incorporated a novel method and apparatus for automatically varying the condenser capacity in accordance with the condensing requirements imposed thereon. This control apparatus consists primarily of a fan IS in which the blades I9 are variable in pitch, and of a mechanism for automatically varying the pitch of said blades I9 in response to the thermal conditions within the condenser I6.

Referring to Figure III the mechanism for varyingv the pitch of the fan blades I9 is composed of a movable piston 3| disposed within the cylinder 32 and connected to the spirally grooved shaft 33 by means of the control rod I8. Conduits 31 and 31' extending from said cylinder 32 to a small venturi 38 disposed in the condenser outlet 28 transmit the differential pressure existing between the inlet 39 and throat 40 of the venturi 38 to said cylinder 32. The spring 4I carried by the control rod I8 exerts a force which opposes the forces exerted by the differential pressure above referred to and tends to maintain the fan blades I9 at low pitch. In operation the dynamic flow of the condensate through the venturi 38 produces a differential pressure which acts upon the piston 3| to overcome the force of the spring 4i, and thus move the fan blades I9 to a higher pitch. This arrangement provides a continuous stable control of the air flow from the fan I6 in accordance with the thermal conditions of the core I0. Under normal operation the pitch of the fan blades I9 remains relatively flat until vapor appears in the Venturi throat 4!] at which time the higher pressures due to said vapor cause the blade pitch to be increased abruptly and the control apparatus becomes very sensitive. Thus the condensate is cooled just below the saturation temperature and the power absorbed by the fan I6 is maintained at a minimum.

The internal construction of the variable pitch blade fan I6 herein illustrated in Figure II is not new in the art and is not deemed essential to this invention. Many such known mechanisms are entirely satisfactory and may be adapted to this use with but slight modification.

The variable pitch hub design shown in Figure II comprises an opposed spirally grooved shaft 33 longitudinally shiftable in a hub 45 forming a gear case driven by the fan shaft 44, on which shaft are mounted driving bevel gears 46 and 41 in spaced facing relationship, both gears meshing with pinions 48 fixed to the inner ends of the fan blades I9. As long as the grooved shaft 33 is not shifted longitudinally, the two gears rotate as a unit with the fan blades, the shaft 33 having a swiveled connection in a bearing 35, longitudinal movement of which, in response to movement of the control rod I8, forcing differential and opposite rotation of the gears 46 and 41, thus turning the fan blades I9 to change their pitch. For example, if the control rod moves to the right in Figure II, as indicated by the arrow 34, the

opposite pitch of the two halves of the spirally grooved shaft 33 will rotate the gears 46 and 41 in opposite'directions to increase the pitch of the fan blades thus increasing the air delivery of the fan. It will be understood that this differential movement of the gears 46 and 41 is superimposed on the normal rotational movement of the fan shaft 44.

An additional protective device or control apparatus is also incorporated herein comprising a reset type electric (micro) switch 42 which is sensitive to the pressure within the condenser core I0, thus if the condenser pressure would abruptly rise to a relatively high value the switch 42 may be utilized to break the circuit to a solenoid operated valve (not shown) disposed in the steam line leading to the turbine I6, such safety apparatus would prevent damage to the condenser II] by the high pressure vapor.

Having fully described the invention in its present preferred embodiments, it is to be understood that many modifications and substitutions may be resorted to in a manner limited only by a just interpretation of the following claims.

I claimf 1. In heat exchange apparatus, the combination of a vapor turbine, an air cooled condenser for condensing the exhaust vapor from said turbine, a fan driven by said turbine for supplying air to said condenser, and a control apparatus responsive to the dynamic flow pressure of the exhaust vapor leaving said condenser so as to vary the quantity of cooling air supplied thereto.

In heat exchange apparatus, the combination of a vapor turbine, an air cooled vapor condenser, a variable pitch blade fan driven by said turbine and disposed so as to supply cooling air to said condenser, and a control apparatus operating in response to the presence of vapor at the condensate end of said condenser to vary the pitch of said fan blades and thereby increase the quantity of condenser cooling air.

3. In heat exchange apparatus, the combination of air cooled vapor condenser, a variable pitch blade fan for supplying cooling air to said condenser, and a control apparatus for varying the quantity of cooling air supplied to said condenser, said control apparatus comprising a venturi disposed in the condenser outlet and a mechanism operating in response to the differentia1 pressure between the inlet and throat of said venturi to vary the pitch of said fan blades.

4. An apparatus as set forth in claim 3 in which said mechanism comprises a cylinder, a movable piston disposed within said cylinder, conduit means conducting said differential pressure to said cylinder, and a fan pitch operating mechanism between said piston and said variable pitch blade fan.

5. In a power plant, the combination of a steam turbine, an air cooled condenser, means for conducting exhaust steam from said turbine to said condenser, a fan with variable pitch blades for supplying cooling air to said condenser, a control apparatus responsive to the pressure at the condensate end of said condenser to vary the pitch of said fan blades and thereby the quantity of cooling air supplied, and a second control apparatus responsive to excessive pressures within the condenser to shut off the supply of steam thereto.

6. In power plant apparatus, the combination of an air cooled vapor condenser, means for supplying vapor at high temperature to said condenser, a fan with variable pitch blades for cooling said condenser, and a control mechanism for varying the pitch of said fan blades and thereby the quantity of cooling air supplied in response to a change in the thermal conditions at the condensate end of the condenser, said control mechanism comprising a venturi disposed in the condensate outlet, a cylinder, a spring loaded movable piston within said cylinder, conduit means extending from the inlet of said venturi to said cylinder and from the throat of said venturi to said cylinder, said piston being actuated by the differential pressure existing between the inlet and throat of said venturi, and a pitch control mechanism extending between said piston and said variable pitch blade fan.

7. In a steam power plant including an air cooled condenser therefor having a condensate outlet, a variable pitch fan of the propeller type driven by said power plant, said fan being adapted to force air into said condenser, a vapor sensitive mechanism associated with the condensate outlet, and means operatively connecting said vapor sensitive mechanism to the pitch varying mechanism of said fan, said connecting means being adapted to increase the pitch of said fan when said vapor sensitive mechanism is energized by the presence of vapor at said condensate outlet.

8. In combination with a steam power plant of the class described, a variable pitch fan driven thereby, a condenser for the steam adapted to be cooled by the air blast from said fan, and mechanism adapted to be energized by vapor in the condensate from said condenser, said mechanism including a connection to the variable pitch fan whereby to increase the delivery thereof in response to the presence of vapor in said condensate.

NATHAN C. PRICE. 

